revert to embedded anonymous images if downloading pictures fails

app/pictures/handler.go

@@ -2,22 +2,47 @@ package pictures
 
 import (
 	"brainbaking.com/go-jamming/db"
+	_ "embed"
 	"github.com/gorilla/mux"
+	"github.com/rs/zerolog/log"
 	"net/http"
 )
 
+//go:embed anonymous.jpg
+var anonymous []byte
+
+const (
+	Anonymous = "anonymous"
+)
+
+func init() {
+	if anonymous == nil {
+		log.Fatal().Msg("embedded anonymous image missing?")
+	}
+}
+
 // Handle handles picture GET calls.
 // It does not validate the picture query as it's part of a composite key anyway.
 func Handle(repo db.MentionRepo) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		picDomain := mux.Vars(r)["picture"]
+		if picDomain == Anonymous {
+			servePicture(w, anonymous)
+			return
+		}
+
 		picData := repo.GetPicture(picDomain)
 		if picData == nil {
 			http.NotFound(w, r)
 			return
 		}
-		w.WriteHeader(http.StatusOK)
-		// TODO response headers? is this a jpeg, png, gif, webm? should we?
-		w.Write(picData)
+		servePicture(w, picData)
 	}
 }
+
+// servePicture writes an OK and raw bytes.
+// For some reason, headers - although they should be there - aren't needed?
+func servePicture(w http.ResponseWriter, bytes []byte) {
+	w.WriteHeader(http.StatusOK)
+	w.Write(bytes)
+}

app/webmention/recv/receive.go

@@ -2,6 +2,7 @@ package recv
 
 import (
 	"brainbaking.com/go-jamming/app/mf"
+	"brainbaking.com/go-jamming/app/pictures"
 	"brainbaking.com/go-jamming/common"
 	"brainbaking.com/go-jamming/db"
 	"brainbaking.com/go-jamming/rest"
@@ -97,16 +98,22 @@ func (recv *Receiver) parseBodyAsNonIndiewebSite(body string, wm mf.Mention) *mf
 	}
 }
 
+// saveAuthorPictureLocally tries to download the author picture.
+// If it succeeds, it alters the picture path to a local /pictures/x one.
+// If it fails, it falls back to a local default image.
+// This *should* also validate image byte headers, like https://stackoverflow.com/questions/670546/determine-if-file-is-an-image
 func (recv *Receiver) saveAuthorPictureLocally(indieweb *mf.IndiewebData) {
 	_, picData, err := recv.RestClient.GetBody(indieweb.Author.Picture)
 	if err != nil {
-		log.Warn().Err(err).Str("url", indieweb.Author.Picture).Msg("Unable to download author picture. Ignoring.")
+		log.Warn().Err(err).Str("url", indieweb.Author.Picture).Msg("Unable to download author picture. Reverting to anonymous.")
+		indieweb.Author.Picture = fmt.Sprintf("/pictures/%s", pictures.Anonymous)
 		return
 	}
 	srcDomain := rest.Domain(indieweb.Source)
 	_, dberr := recv.Repo.SavePicture(picData, srcDomain)
 	if dberr != nil {
-		log.Warn().Err(err).Str("url", indieweb.Author.Picture).Msg("Unable to save downloaded author picture. Ignoring.")
+		log.Warn().Err(err).Str("url", indieweb.Author.Picture).Msg("Unable to save downloaded author picture. Reverting to anonymous.")
+		indieweb.Author.Picture = fmt.Sprintf("/pictures/%s", pictures.Anonymous)
 		return
 	}
 

app/webmention/recv/receive_test.go

@@ -22,6 +22,48 @@ var conf = &common.Config{
 	ConString: ":memory:",
 }
 
+func TestSaveAuthorPictureLocally(t *testing.T) {
+	cases := []struct {
+		label              string
+		pictureUrl         string
+		expectedPictureUrl string
+	}{
+		{
+			"Absolute URL gets 'downloaded' and replaced by relative",
+			"https://brainbaking.com/picture.jpg",
+			"/pictures/brainbaking.com",
+		},
+		{
+			"Absolute URL gets replaced by anonymous if download fails",
+			"https://brainbaking.com/thedogatemypic-nowitsmissing-shiii.png",
+			"/pictures/anonymous",
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.label, func(t *testing.T) {
+			repo := db.NewMentionRepo(conf)
+			recv := &Receiver{
+				Conf: conf,
+				Repo: repo,
+				RestClient: &mocks.RestClientMock{
+					GetBodyFunc: mocks.RelPathGetBodyFunc(t, "../../../mocks/"),
+				},
+			}
+
+			indieweb := &mf.IndiewebData{
+				Source: "https://brainbaking.com",
+				Author: mf.IndiewebAuthor{
+					Picture: tc.pictureUrl,
+				},
+			}
+			recv.saveAuthorPictureLocally(indieweb)
+
+			assert.Equal(t, tc.expectedPictureUrl, indieweb.Author.Picture)
+		})
+	}
+}
+
 func TestReceive(t *testing.T) {
 	cases := []struct {
 		label string

mocks/restclient.go

@@ -50,7 +50,7 @@ func RelPathGetBodyFunc(t *testing.T, relPath string) func(string) (http.Header,
 		mockfile := relPath + strings.ReplaceAll(url, "https://brainbaking.com/", "")
 		html, err := ioutil.ReadFile(mockfile)
 		if err != nil {
-			t.Error(err)
+			return nil, "", err
 		}
 
 		headerData, headerFileErr := ioutil.ReadFile(strings.ReplaceAll(mockfile, ".html", "-headers.json"))